Active clinical trials for "Refractive Errors"

This will be an up to six months, subject-masked, contralateral, parallel-group, randomised, daily wear study. All subjects will wear the Test lens in one eye and the Control lens in the other eye. Data from the first four weeks of Test and Control lens exposure will be used for the FDA 510 (k) submission.

The aim of this study is to analyze the results of PresbyLASIK performed using the wavefront-optimized LASIK for the treatment of presbyopia on low hyperopic and low myopic patients with astigmatism. Visual performance will be assessed using clinical outcome measures of the following: refraction, near, intermediate and distance visual acuity, stereoacuity and contrast sensitivity. Questionnaires will also be used to evaluate how the patient's vision is before and after surgery.

The purpose of this study is to compare the fit characteristics between four Alcon commercially available toric contact lenses.

The purpose of this study is to evaluate the safety and efficacy of FID 120947A in soft contact lens wearers of Japanese ethnicity.

The purpose of this study is to evaluate the incidence of ocular discomfort device-related adverse events with DAILIES TOTAL1® with UV Absorber (DT1 UV) contact lenses compared with current DAILIES TOTAL1® (DT1) contact lenses.

Some programs do the screening, refraction testing and provision of spectacles to children entirely in the school setting ("School Model"). One strength of such programs is that most children at school who need spectacles get them. However, sustainability is poor, because spectacles cannot be sold in many schools and there may be too few refractionists to cover all schools in most countries. Other programs provide vision screening at schools but refer children who fail vision screening to nearby facilities for refraction and distribution/sale of spectacles ("Referral Model"). This model's strengths include a lower demand for refractionists and opportunities for the spectacles to be sold. However, a disadvantage is that most of the referred children do not attend the specialist facility. One way to improve this might be to enhance the Referral Model and a recent USAID review by Priya Reddy and Ken Bassett showed that involving teachers in vision screening and family counseling significantly increases children's use of spectacles. Therefore, at 141 schools in India, involving over 42,300 children (assuming a minimum of 300 children/school), the investigators will study an "Improved Referral Model," with strong teacher involvement, to investigate the potential benefits of combining the lower costs of the "Referral Models" with the high uptake of the "School Model". The investigators will also assess the effects of allowing parents to purchase enhanced spectacles, rather than having their child use free spectacles. Children will be randomized by the school to the "School Model," "(Improved) Referral Model" or the "(Improved) Referral Model + Cost Recovery (sale of "upgrade spectacles" alongside offering free spectacles. The main study outcome will be program cost-effectiveness, defined as the program cost per child identified with correctable refractive error, who receives spectacles, and wears them at an un-announced visit between 8 to 12 weeks after distribution. Profit on spectacles sold in the "Referral + Cost Recovery" group will be subtracted from the program costs in this study group. The groups will be compared, with and without adjustment for baseline characteristics.

The purpose of this study is to evaluate the initial safety of the UV-FS laser in humans.

The purpose of this study is to utilize in-vivo confocal microscopy to describe differences in corneal epithelial immune status across three lens care regimens in new contact lens wearers.

The Baltimore Reading and Eye Disease Study (BREDS) is a two year study to determine the prevalence of vision problems in an early school age population with reading difficulty. Comprehensive vision and reading tests will be administered to 400 students at participating schools in the Baltimore City Public School system. A secondary goal is to examine the impact of vision treatment on reading performance. Children with refractive error or convergence insufficiency will be provided treatment free of charge. The investigators will evaluate the impact that the treatment has on vision function and reading performance.

The purpose of this study is to demonstrate that omega-3 supplement can be use as an adjunct therapy for PRK patients. The investigators believe that omega-3 supplement will reduce the size of persistent epithelial defects (PEDS) and eventually hasten the corneal reepithelialization after PRK surgery. If the outcome of this study proves to be effective, then PRK would be a more attractive option to those seeking refractive treatment.